When to change Battery

[mansour Member Find all posts View Profile Close mansour]

Dear Mates

As of my last visit to do a 5k service the agent tells me that my Battery reads 9Volts and it will be time to change the battery soon

I took a look at the battery indicator and it still shows blue background and a red dot which means -according to the battery's legend- Good

The car has been with me for 2.5 years and has 48K on the dot

What do you think mates ?

PS: Sorry if this sounds like a double post but I couldn't find a similar case in y humble search

[IRON-PAWW Avid PP Poster! Find all posts View Profile Close IRON-PAWW]

Always hard to tell with batteries in my experience. Back when I was an agricultural man, 2 years was about the limit for standard batteries. But then, we used to hit them pretty hard. All you can do is check that each cell isn't getting low too rapidly and consistently. That points to oncoming death for a battery. If you have one, you can also attach a voltmeter and see what reading you're getting from it. Modern engines need a fair amount of cranking power so you often don't seem to get as many "warnings" that your battery is dying as you used to. Some old petrols would limp over on the starter and still fire. High compression diesels in particular wont tolerate much of a loss in cranking power before you start getting that Click click Click on the starter instead of cranking.

For a standard battery, 2.5 years is a good innings in my experience and if that was me I'd be thinking about swapping it out. Once again though, I'm not a mechanic, but I wasn't born yesterday either.... 8)

[leachy_9 Advanced Member Find all posts View Profile Close leachy_9]

the agent tells me that my Battery reads 9Volts

I'd be questioning this statement. If your battery was at 9V it is most probably stuffed (assuming the charging circuit is working) and I doubt it would crank the engine.
Take it to a battery specialist for load testing.

leach

[Zapper Member Find all posts View Profile Close Zapper]

If the battery is reading 9 volts you will know about it because you would be having trouble starting the car. If you have a multimeter handy check it out for yourself. Mine reads 12.4volts and 14volts when the engine is running.
I haven't changed the battery yet and its over 4years old.

[PK Lurker Find all posts View Profile Close PK]

I have just changed my battery at almost 5yrs... 80,000 km It was getting very dodgy..

An interesting thing happened to the Grande Trip Meter though. Before new battery when full to the brim with fuel (180 litres diesel) my Readout never seemed to go above 1150km or so. After the battery install it now reads about 1350 km. I wonder what happened there.... :?:

PK.

2003 Grande TD

[waltec Senior Member Find all posts View Profile Close waltec]

An interesting thing happened to the Grande Trip Meter though. Before new battery when full to the brim with fuel (180 litres diesel) my Readout never seemed to go above 1150km or so. After the battery install it now reads about 1350 km. I wonder what happened there.... :?:

PK.

2003 Grande TD

My educated guess would be that the Trip computer does an analogue to digital (A to D) conversion of the fuel guage, compares it to the consumption figure and calcualtes the range. A to D conversions are very voltage sensitive, so maybe with the battery failing the voltage had dropped enough to upset this conversion and therefore the range figure.

Matt

[johna Member Find all posts View Profile Close johna]

Just changed mine, 125,000 and 4years 11 months.
As stated above, 9 volts will definately not crank over a diesel.
Suggest you check it again with a different voltmeter.

John

[Steve & Sandra Senior Member Find all posts View Profile Close Steve & Sandra]

Has anybody heard of a Hydrometer?

[Chippy Addicted PP Member Find all posts View Profile Close Chippy]

Has anybody heard of a Hydrometer?

Yeah mate ... I used to use one to check my dinosaur's fluid levels before heading off on the hunt. :lol: :lol: :lol:

Cheers
Chippy

[Steve & Sandra Senior Member Find all posts View Profile Close Steve & Sandra]

What are you trying to say Chippy? As a first year apprentice it was one of the first tools we was let loose on.

[IRON-PAWW Avid PP Poster! Find all posts View Profile Close IRON-PAWW]

The old "Hydrometer on the apprentices" trick huh? Good substitute for an IQ test I suppose. However, the mere mention of "acid" these days seems to have undesirable effects on apprentices.......

[Chippy Addicted PP Member Find all posts View Profile Close Chippy]

Mention "acid" in a high school and you get a bigger queue than the canteen. :lol: :lol:

Cheers
Chippy

[plucker Advanced Member Find all posts View Profile Close plucker]

Hydrometer will give the most accurate diagnosis for the state of the wet cell lead acid battery. If the voltage is ok and one cell is getting low, then the battery is on the way out.
Load testing batteries with load banks can give inaccurate results. The load test might pass, but the battery might be near the end of its life and this might be the final gasp of its life. The battery might die days after this test even though it passed previously.
Your batteries life will depend on several factors.
1. Sufficient electrolyte levels are maintained throughout the batteries life.
2. Sufficient charge from the cars alternator regularly.
3. Major current draws are reduced or limited. eg less starts for more KM's and properly functioning and use of glow plugs in diesel engines for starting help prolong the life.
4. the amount of vibration during the batteries life.
5. the temperature the battery is exposed to. Most batteries die in winter on that icy cold morning.

[yetiboy01 Senior Member Find all posts View Profile Close yetiboy01]

Anything under 10.5 volts & the battery is dead flat & wont crank your engine to start.
The best test for the battery is testing it under load with a load test meter, most battery suppliers or auto sparkys should have one & the test only takes a few seconds